Process control system
View Patent ↗The disclosed process control system makes use of Optimal control (OC) and model predictive control (MPC) techniques for selection of the Expert Systems (ES) targets values U. The ES target values U are selected to minimize the performance criterion J. A mathematical model of an extended system given by the process P and the ES is developed. This hybrid mathematical model has both continuous dynamics and logical relationships. Controlled variables of the mathematical model are the ES target values U and inputs are the measurements y and the performance criterion J. The OC and/or MPC techniques are used to compute values U. An optimizer of the OC/MPC selects values of the ES target values U only. This activity has lower sampling rates than selection of controller values, which simplifies the design of the OC/MPC controller.
1. A process control system, comprising
an expert system that models the actions of an operator of the process over an operating region of the process, that represents a set of rules for actions to be taken by an operator upon the occurrence of predetermined conditions in the operation of the process in order to meet given process targets, and that takes the action when one of the predetermined conditions exist to control the operation of the process by changing one or more of process control variables that control the process following the set of rules; and,
a model predictive control system that is operable to receive inputs representing measured variables of the process and to predict on an output of the model predictive control system predicted control values for controlled variables that control the process;
wherein the model predictive control system and the expert system are series connected in such a way that predicted control values of the model predictive control system serve as process targets for the expert system.
2. The process control system of claim 1 , wherein the model predictive control system controlling the process targets for the expert system is supervised by another expert system.
3. The process control system of claim 2 , wherein several layers of model predictive control systems and expert systems are series connected.